During the drilling or completion of an oil and gas well, the walls of oil and gas formations are often exposed to wellbore fluids which may damage producing formations. To prevent such damage, a wellbore often requires the deposit of a low-permeability filter cake on the walls of the wellbore to seal the permeable formation exposed by the drilling operation. The filter cake functions to limit drilling fluid losses from the wellbore as well as protect the formation from possible damage by the fluids filtering into the walls of the wellbore. Solids, such as particulate fines, suspended in the drilling fluid may also contribute to damaging hydrocarbon producing formations.
To protect formations from damaging fluids and solids, a filter cake may be formed and/or deposited on the surface of the subterranean formation. Filter cakes are typically formed when particles suspended in a wellbore fluid coat and plug the pores in the subterranean formation such that the filter cake prevents or reduces both the loss of fluids into the formation and the influx of fluids present in the formation. A number of ways of forming filter cakes are known in the art, including the use of bridging particles, cuttings created by the drilling process, polymeric additives, and precipitates.